RF squarer circuits require a certain amount of gain, for example a significant amount of gain. For example, if the input signal has an amplitude A<1V (as may be typical in the case of modern integrated circuits), its power of two (A2) is a signal that is about an order of magnitude smaller than A:                e.g., where A=100 mV; A2=10 mV.A high gain can be achieved using a cascade of amplification stages with the drawback that each stage requires power and generates noise. For low noise applications, the number of active devices used may be reduced.        
High gain can be achieved with a TIA by increasing the resistance of feedback resistors. However, increasing the gain reduces the bandwidth at the same time, due to a pole created together with parasitic capacitances. In addition, the gain achieved by an RF squarer may vary significantly over process, voltage and temperature (PVT). In some applications, a variation of up to at least 10 dB may be expected. Accordingly, there is a need for an RF Squarer with relatively high gain while reducing bandwidth loss.